Energy demands are increasing not only in the United States, but worldwide as well. Energy in the form of electricity and petroleum including fuels such as gasoline and diesel, natural gas, and heating oil, are becoming more expensive. This is in part due to increasing demand throughout the world notwithstanding efforts to conserve. In addition, sources of energy products are becoming more difficult to obtain and require enhanced technology for recovering. Refineries presently operate at close to capacity levels. Coal plays an important role; however, coal also has intense labor requirements and necessary post burning filtering and cleaning of exhaust and water. Nuclear electrical generation plants are being viewed again favorably, and a significant percentage of electrical energy is generated using such plants worldwide.
In addition to conventional sources of electrical energy, other alternative generation systems are available. These include hydroelectric, oceanic involving thermal and mechanical transfers of energy, wind power, and solar. These alternate forms of electrical generation presently tend to be more expensive per kilowatt hour than more conventional sources. However, as demand for energy increases, alternative energy sources become increasingly attractive for environmental and cost reasons. Further, as costs for equipment, installation, and maintenance of these alternative systems decrease (or increases moderate), as well as incentives from manufacturers and governments for such alternative sources, these alternative sources become more attractive for use.
The effectiveness of solar systems for electrical generation or heating of water depends upon the particular site for which solar energy generation is to be utilized. Visual assessments and manual estimates provide some indication as to the desirability of a site for solar energy generation. Further, a tool has been developed using a reflector dome and astronomical grid to record a sun track relative to a particular site. The sun track is evaluated for determining annual solar capacity for evaluating the opportunity and economics of a particular site for solar energy.
This analysis device positions a template having a latitude band for a specific geographic location under a transparent dome. The device is positioned where the solar energy capacity is to be determined for a solar collector. The surrounding area reflects onto the template. The template includes grid lines for time of day and time of year. A trace is made of the curve of the reflection on the paper template to render a trace for the particular site.
The lines on the template are specific to the latitude band. Columns represent half hour increments and rows represent months of year. To determine the amount of solar exposure, the unshaded half hour sections are summarized. A percent solar exposure is determined. The site percent value is converted to kilowatt hours per square meter per day. This conversion is based on comparing the site solar capacity with data values of a selected comparable unobstructed site. The National Renewable Energy Lab provides solar radiation energy level data for various weather stations as recorded over an extended number of years. The website on the World Wide Web http://rredc.nrel.gov/solar/codes_algs/PVWATTS/version1 provides access to this data as well as analysis software.
While this approach reaches a solution as to potential solar opportunity, the solar site analysis tools experience drawbacks to its use. The device and analysis is subject to error and is time consuming to use. The analysis lack precision and flexibility of use, particularly for evaluating a site and making recommendations for changes in order to enhance the solar profile of the site. Accordingly, there is a need in the art for apparatus and methods that facilitate selection, evaluation, and modification of sites for reception of solar energy. It is to such that the present invention is directed.